Helium-3, a rare isotope of helium gas, is leaking out of Earth’s core
#1

Helium-3, a rare isotope of helium gas, is leaking out of Earth’s core, a new study reports. Because almost all helium-3 is from the Big Bang, the gas leak adds evidence that Earth formed inside a solar nebula, which has long been debated.

Helium-3 has been measured at Earth’s surface in relatively small quantities. But scientists did not know how much was leaking from the Earth’s core, as opposed to its middle layers, called the mantle.

The new study published today (March 28, 2022) in Geochemistry Geophysics Geosystems, pins down the core as a major source of helium-3 on the Earth. Some natural processes can generate helium-3, such as the radioactive decay of tritium, but helium-3 is made primarily in nebulae — massive, spinning clouds of gas and dust like the one that gave rise to our Solar System. Because helium is one of the earliest elements produced in the universe, most helium-3 can be traced back to the Big Bang.

As a planet grows, it accumulates material from its surroundings, so its composition reflects the environment in which it formed. To get high concentrations of helium-3 deep in the core, Earth would have had to form inside a thriving solar nebula, not on its fringes or during its waning phase.

The new research adds further clues to the mystery surrounding Earth’s formation, lending additional evidence to the theory that our planet formed inside the solar nebula.

The study was published in the AGU journal Geochemistry, Geophysics, Geosystems,
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#2

About 2,000 grams of helium-3 leak out of the Earth every year, “about enough to fill a balloon the size of your desk,” said lead study author Peter Olson, a geophysicist at the University of New Mexico. “It’s a wonder of nature, and a clue for the history of the Earth, that there’s still a significant amount of this isotope in the interior of the Earth.”

The researchers modeled helium during two key stages of Earth’s history: early formation, when the planet was accumulating helium, and following the formation of the Moon, after which helium was lost. Evidence suggests an object one-third the size of the Earth hit the planet early in its history, around 4 billion years ago and that impact would have re-melted the Earth’s crust, allowing much of the helium to escape. The gas continues escaping to this day.

Using the modern helium-3 leak rate along with models of helium isotope behavior, the researchers estimated there are between 10 teragrams (1013 grams) to a petagram (1015 grams) of helium-3 in the core — a vast quantity that Olson said points to Earth’s formation inside the solar nebula, where high concentrations of the gas would have allowed it to build up deep in the planet.

However, future work looking for other nebula-created gases, such as hydrogen, leaking in similar rates and locations as helium-3 could be a “smoking gun” for the core as the source, Olson said. “There are many more mysteries than certainties.”
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#3

Evidence suggests surface minerals of outer main-belt asteroids, proposed to have sourced building blocks of Earth’s water and life, are only stable at low temperatures. These asteroids formed in distant orbits and may help explain Earth’s composition.

Our Solar System is believed to have formed from a cloud of gas and dust, the so-called solar nebula, which began to condense on itself gravitationally ~ 4.6 billion years ago. As this cloud contracted, it began to spin and shaped itself into a disk revolving about the highest gravity mass at its center, which would become our Sun.

Our solar system inherited all of its chemical composition from an earlier star or stars which exploded as supernovae. Our Sun scavenged a general sample of this material as it formed, but the residual material in the disk began to migrate based on its propensity to freeze at a given temperature. As the Sun grew dense enough to initiate nuclear fusion reactions and become a star, it scavenged a general sample of this material as it formed, but the residuals in the disk formed solid materials to form planetary bodies based on its propensity to freeze at a given temperature.

As the Sun irradiated the surrounding disk, it created a heat gradient in the early solar system. For this reason, the inner planets, Mercury, Venus, Earth, and Mars, are mostly rock (mostly composed of heavier elements, such as iron, magnesium, and silicon), while the outer planets are largely composed of lighter elements, especially hydrogen,


https://scitechdaily.com/meteorites-that...medium=cpc&utm_source=TrendMD&utm_campaign=SciTechDaily_TrendMD_0
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#4

Breath helium can sound like Donna duck.
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#5

Earth is believed to have formed partly from carbonaceous meteorites, which are thought to come from outer main-belt asteroids. Telescopic observations of outer main-belt asteroids reveal a common 3.1 µm reflectance feature that suggests their outer layers host either water ices or ammoniated clays, or both, which are only stable at very low temperatures. Interestingly, though several lines of evidence suggest carbonaceous meteorites are derived from such asteroids, the meteorites recovered on Earth generally lack this feature. The asteroid belt thus poses many questions for astronomers and planetary scientists.

A new study led by researchers at the Earth-Life Science Institute (ELSI) at Tokyo Institute of Technology suggests these asteroidal materials may have formed very far out in the early Solar System then been transported into the inner Solar System by chaotic mixing processes. In this study, a combination of asteroid observations using the Japanese AKARI space telescope and theoretical modeling of chemical reactions in asteroids suggests that the surface minerals present on outer main-belt asteroids, especially ammonia (NH3)-bearing clays, form from starting materials containing NH3 and CO2 ice that are stable only at very low temperature, and under water-rich conditions. Based on these results, this new study proposes that outer main-belt asteroids formed in distant orbits and differentiated to form different minerals in water-rich mantles and rock-dominated cores.
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#6

If true, this study suggests that Earth’s formation and unique properties result from peculiar aspects of the Solar System’s formation. There will be several opportunities to test this model, for example, this study provides predictions for what the analysis of Hayabusa 2 returned samples will find. This distant origin of asteroids, if correct, predicts that there will be ammoniated salts and minerals in Hayabusa 2’s returned samples. A further check on this model will be provided by the analyses of returned materials from NASA’s OSIRIS-Rex mission.

This study also examined whether the physical and chemical conditions in outer main-belt asteroids should be able to form the observed minerals. The cold and distant origin of asteroids proposed suggests there should be a significant similarity between asteroids and comets and raises questions about how each of these types of bodies formed.

This study suggests the materials that formed the Earth may have formed very far out in the early Solar System and then been brought in during the especially turbulent early history of the solar system. Recent observations of protoplanetary disks by the Atacama Large Millimeter/submillimeter Array (ALMA) have found many ringed structures, which are believed to be direct observations of planetesimal formation.
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#7

(30-03-2022, 03:52 PM)Migrant Wrote:  Breath helium can sound like Donna duck.

Lead author Hiroyuki Kurokawa summarizes.

“Our solar system’s formation is a typical outcome remains to be determined, but numerous measurements suggest we may be able to place our cosmic history in context soon.” Smile
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#8

Cham..the earth is sick.

Do not talk to a fool for he will scorn  the wisdom of your words 
☝️
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#9

(30-03-2022, 07:09 PM)Lukongsimi Wrote:  Cham..the earth is sick.
Atacama Large Millimeter/submillimeter Array (ALMA) is an astronomical interferometer of 66 radio telescopes in the Atacama Desert of northern Chile, which observe electromagnetic radiation at millimeter and submillimeter wavelengths. 

The array has been constructed on the 5,000 m (16,000 ft) elevation Chajnantor plateau - near the Llano de Chajnantor Observatory and the Atacama Pathfinder Experiment. 

Location was chosen for its high elevation and low humidity, factors which are crucial to reduce noise and decrease signal attenuation due to Earth's atmosphere.

ALMA is expected to provide insight on star birth during the early Stelliferous era and detailed imaging of local star and planet formation.
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